During the last decade, a demand has become more and more pronounced to prevent the loss of teeth or groups of teeth instead of substituting them by removable prostheses.
Because of the disease of the periodontium, the alveolar walls and thereby the mandibles atrophy after removal or loss of a tooth or teeth being close to each other. The solid fixation of a metal implant in atrophied, bone-deficient jaws is problematic.
In the cases of certain diseases, e.g. bone tumors, the bone defect is artificially established by removing the tumor tissue or by a bone fracture.
It is known that porous hydroxylapatite (e.g. CEROS.sup.R 80) or tricalcium phosphate (e.g. CEROS.sup.R 82), respectively are useful bone-substitutive materials in dentistry and maxillary surgery. The drawback of this method consists in that after filling the bone-defective region with a porous hydroxylapatite or tricalcium phosphate by suitable techniques, an amount of new bone providing a safe implantation bed has formed only after 20 months.